Here is a spreadsheet that will work out damage done to a wall
with your cards. It will take into account the reductions applied
while attacking the wall (currently calculated at 5%), and then the
increase applied by the bonuses.

Wallbreaker Calculations (Google Doc)

How to use -

Hopefully the list of wallbreaker cards are up to date

Select your 5 cards by either using the dropdown list to select
a wallbreaker, or you can just type any card name in.

Level Stats Google DocIf you do help out, feel free to leave
your name on the front page so I can give thanks to you.

Here is my page devoted to finding a formula (at least an
approximate formula) for the Card Stats.

How many times have you been offered a fuse card that is mid
level and you have no idea whether it is fused correctly. Sometimes
its easy to tell because the mastery is at a level below what the 2
cards fused should be (like 1/150). The end use of this will be to
help establish whether a card is fused correctly.

Its mean the mastery is above the minimum level that it becomes
rather had to determine.

So far I know that there is at least 2 formulas used to work out
the base stats.